Disk drive manufacturers typically test manufactured disk drives for compliance with a collection of requirements. Test equipment and techniques exist for testing large numbers of disk drives serially or in parallel. Manufacturers tend to test large numbers of disk drives simultaneously or in batches. Disk drive testing systems typically include one or more racks having multiple test slots that receive disk drives for testing.
The testing environment immediately around the disk drive is closely regulated. Minimum temperature fluctuations in the testing environment are critical for accurate test conditions and for safety of the disk drives. The latest generations of disk drives, which have higher capacities, faster rotational speeds and smaller head clearance, are more sensitive to vibration. Excess vibration can affect the reliability of test results and the integrity of electrical connections. Under test conditions, the drives themselves can propagate vibrations through supporting structures or fixtures to adjacent units. This vibration “cross-talking,” together with external sources of vibration, contributes to bump errors, head slap and non-repetitive run-out (NRRO), which may result in lower yields and increased manufacturing costs.
Test slots of disk drive testing systems require routine validation and diagnostic testing to insure that the test slots are functioning and performing properly. In general, a “gold drive” is a disk drive that has been independently validated as functioning and performing properly. The gold drive may be used to test the functionality and performance of test slots. Validating and maintaining verification of the gold drive's veracity is cumbersome and expensive. Furthermore, testing data is limited.